Centrifuges typically include a housing with a centrifuge chamber, a rotor and drive spindle that supports samples to be centrifuged, a rotor cover and a chamber door. The centrifuge chamber within which the rotor rotates is covered by the chamber door during centrifugation to protect the centrifuge operator from the spinning parts in the chamber. The chamber door also provides containment should material be projected from the rotor during rotor rotation. The rotor cover encloses the samples inside the rotor and provides an aerodynamic smooth surface to reduce air friction during operation. The rotor cover is moveable between an open and closed position. The open position accommodates access to the rotor and while in the closed position the cover encases the rotor.
During normal centrifuge operation, a liquid sample is disposed and sealed within a receptacle, usually a centrifuge sample tube, and the tube is placed within holes located on the rotor. Thereafter, the rotor cover is placed in the closed position, covering the rotor and readying the centrifuge for operation. Occasionally the centrifuge tubes may leak. This leakage can result from improper sealing of the tube, using a tube not rated for the rotor operating speed, and/or using a tube composed from material that is chemically incompatible with the sample. As a result of the aforementioned leakage, the centrifuge components may become contaminated with the samples.
In existing centrifuges, the rotor cover is designed as a separate piece or unit from the rotor and requires manual attachment and detachment for each use. One current method for attachment includes utilizing a captive nut on the rotor cover that is screwed onto a threaded post located on the center of the drive spindle of the rotor. Another current method includes utilizing clamping studs, each having threaded members, wherein the studs are inserted into receiving portions on the rotor and drive spindle and rotated several times to secure the cover to the rotor and the rotor to the drive spindle.
Current rotors have threaded clamping studs; one is used to attach the cover to the rotor and the other is used to attach the rotor to the drive spindle. These studs are oriented in series such that the rotor to drive spindle clamping stud must be disengaged first and then the cover to rotor clamping stud must be disengaged. The cover can then be removed to gain sample access. A problem that sometimes occurs in the operation of these covers is that they are time consuming to operate because many employ multiple threaded parts that each are required to be rotated multiple times to attach the cover to the rotor and the rotor to the drive spindle. Each attachment piece must be manipulated by the centrifuge operator in order to ensure the cover is securely attached to the rotor prior to centrifuge operation and subsequently disengaged after centrifuge use, preventing the centrifuge operator from gaining access to his or her samples quickly and efficiently.
In view of the foregoing, it is desirable to provide a rotor cover for effectuating quick, efficient access to the rotor of the a centrifuge. It is also desirable to provide secure attachment and detachment of a centrifuge rotor cover, employing a minimum number of steps and components.